When considering a masonry chimney, round tiles are preferable to square or rectangular, as round tiles have much better airflow characteristics and are far easier to clean. Unfortunately, most North American chimneys use square or rectangular tile liners that are really designed for open fireplaces, not stoves or furnaces. Of most importance, second only to overall chimney height, is the diameter of the flue liner itself. In most instances, it should be sized to the appliance; i.e., 6" flue outlet on the appliance requires a 6" chimney. The inner diameter should never be less than the
Masonry chimneys built of concrete blocks with or without flue liners do not meet modern building codes. A solid fuel appliance must not be joined to a chimney flue which is connected to another appliance burning other fuels.
If your chimney has a typically oversized flue liner of, say 8 x 12 inches, or greater, or if it is unlined, it will be necessary for you to reline the chimney, using any of the modern approved and economical methods such as stainless steel, castable refractory, or properly sized fireclay linings.
If you have any questions regarding venting your appliance, feel free to contact the factory at the address and phone number on this Owner's Manual. You may also contact NFPA (National Fire Protection Association) and request NFPA Standard 211 (1984
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